A refrigerator includes a shelf in an internal space of a cabinet of the refrigerator. A shelf is installed to efficiently use an internal space of a refrigerator. When the shelf is installed, the internal space of the refrigerator is divided into a plurality of spaces with the shelf as a boundary. Particularly, since a shelf including a bottom plate manufactured using glass or a transparent synthetic resin material has a shape with the bottom plate that is closed, it is difficult to expect a smooth air flow between plurality of divided spaces divided by the shelf.
Accordingly, air cooled by an evaporator installed in a refrigerator is forcibly moved to the plurality of divided spaces and is uniformly distributed into each of the divided spaces to cool the internal space of the refrigerator. That is, the air cooled by the evaporator is pressurized by a fan to move through a duct installed on a rear side of an inner wall of a cabinet and to be supplied to each of the divided spaces through outlets formed at intervals in a path of the duct.
FIG. 1 illustrates an example multi-duct coupled to a cabinet of a refrigerator. An internal space of a cabinet of the refrigerator is divided into first to fourth spaces 51, 52, 53, and 54 by shelves. Also, a multi-duct 80 is installed in a center of a rear side of the cabinet of the refrigerator, in a vertically extending shape as shown in the drawing.
A flow channel 82 is provided in the multi-duct 80 in a vertical direction. A lower end of the flow channel is an entrance of the duct and becomes an inlet through which air cooled by a cooling apparatus such as an evaporator installed at a bottom of a rear side of the refrigerator and pressurized by a fan flows. The air that flows from a bottom of the multi-duct moves upward along the flow channel 82 and sequentially flows into the spaces 54, 53, 52, and 51 in the cabinet through outlets 94, 93, 92, and 91, respectively.
FIG. 2 illustrates example flow and speed of air from a first outlet to a first space a refrigerator. In FIG. 2, air is discharged from a first outlet 91 to a first space 51 through the multi-duct 80 of FIG. 1. FIG. 3 illustrates an example flow and speed of air from a second outlet to a second space in a refrigerator. In FIG. 3, air is discharged from a second outlet 92 to a second space 52.
As shown in FIG. 2, the air discharged through the first outlet 91 is discharged less amount despite a large size of the outlet and discharged to be collected at a center of the space. Accordingly, a temperature of a central area of the first space 51 is low but on the other hand, a temperature of a periphery, particularly a rearward periphery, is relatively high. Due to a structure of the first outlet 91 through which the air is discharged to be collected at the center while the velocity of the air is not high, a temperature difference between a central part and a rearward peripheral space in the first space 51 may be high.
Next, as shown in FIG. 3, the air discharged through the second outlet 92 flows at a lower velocity than that of the air discharged through the third and fourth outlets that are present further upstream of the flow but is intensively discharged in a linear shape. Accordingly, the air in the second space 52 is not smoothly mixed and ultimately temperatures of all areas in the space may be uneven and a temperature difference may be increased depending on position.
Also, even though the first outlet 91 and the second outlet 92 have considerable cross sectional areas, temperatures of the first space 51 and the second space 52 are measured to be slightly higher than temperatures of the third space 53 and the fourth space 54.